Digging machine for root crops



May 26, 1936. J. c. LITTLE 2,042,232

DIGGING MACHINE FOR ROOT CROPS Filed Jan. 18, i935 Fray- 2. g5/35 z2 4o 477 2T bgg gr/- --Vg 41@ 441046 o n 25 5 50 /5 /z j@ f6 a 6 d i sy? 44 f il v n INVENTOR LL BWM l ATTORNEY Patented May 26, 1936 UNITED STATES ATENT OFFICE 3 Claims.

Thisinvention relates to a digging machine for root'crops,.such as potatoes and the like.

The principal objects of my invention are to provide van implement embodying improvements i5 which shall:

First. Effect a, substantial saving in power.

Second. Reduce to a minimum, mechanical injury to potatoes or other root cro-ps in the handling` thereof during `the process of digging.

Third. Besimplerandless expensive to manufacture than implements for a like purpose, as heretofore constructed.

Implements known as po-tato diggers of different kinds, have been .on 4themarket for aconsiderable number of years, andar-e in rather extensive use. Such diggers, while varying somewhat .in .details of construction, include Yin general, `two traction wheels .spaced axially apart from each other, and having a digger blade disposed some .distance in. advanceof the traction wheels. In all types of diggers .of which I am aware, a so-called conveyor web is located at the rear of the digger blade,and as heretofore constructed, isinclined upward and Vback, so as to carry the potatoes .over the axis of the traction Wheels.

Afterbeing carried over the axis of the wheels, the-potatoes lare discharged at a point considerably above, and back, of the traction'wh-eel axis. From this point the potatoes drop onto a second conveyor web which slopes towards the ground, in most vcases rather abruptly. Both these conveyor webs are driven from a shaft located at the discharge end of the first conveyor web, this shaft being suitably intergeared with the traction wheels.

The conveyor webs consist usually of 'iron bars about inch and g inch in diameter, and spaced apart from one another a suitable distance so that the earth maybe shaken away from the potatoes while the :potatoes themselves are carried back, and are deposited on top of the ground. These conveyor webs require considerable power rto drive them, vand under average conditions, :each :potato digger 'requires .six large horses to perform `the digging operation.

lSuch an excessivel lconsumption of power, I have iobservedis due to the unnecessarily Vlong conveyor webs, and to the relatively hlgh'point to which the potatoes and muchof the accompanying earth, must be lifted. The longtravel 'and Ldrop vof fthe conveyor websfresults `in me- :chanical injury to the potatoes, 4such injury being especially-noticeablefwith varieties Vthat have 155 `atender skins :and .are crisp 'intexture In my improved machine, I place the drive shaft for theconveyor webs a considerable distance below the horizontal vplane of the traction wheel axis, as well as aconsiderable distance in front of this axis. This shortens the two con- 5 veyor webs materially, as well as reduces the elevation to which the potatoes must be lifted, since the point of discharge ofthe first conveyor web allows the potatoes to pass in front of, land under, the traction wheel axle, while the second l0 conveyor web, which receives the potatoes from the first one, is located very close to the ground, and haslittle slope.

Thus, by means of my invention, the potatoes or other roots, are ldischargedby .the second-.con- 1.5 veyor web immediately back of the ltraction wheels, andare deposited'on-the ground with only a slight drop. In theY existing types of machines, on the contrary, the potatoes are bumped down over the ,rather steepy slope of the second con- 20 veyor, and dropped off far behind the vtraction wheels with considerable force, which, together withthe long traveLrresults vin excessive mechanical injury. By mechanical injury is meant bruising the potatoes .and/or splitting them to 25 suchan extent that they are not salable in the .higher grades, but, if disposed of at all, must be classed Yas culls.

The features of my invention for which the protection of Letters Patent of the 'United States 3Q Vis desired, are collectively grouped in the claims concluding .this specification.

`In the drawing,

Fig. 1 represents the plan of my improved digging implement;

Fig. 2, a side elevation thereof, with the blade in the digging position, showing the ground ,in front of the blade, in section along line 2-2 in Fig. l; and Y Fig. 3, a diagram showing `more clearly the 40 relative disposition of the conveyor webs.

Referring to the drawing, the numeral Illv denotes the `usual traction wheels mounted on an axle I2, and provided with traction cleats I4. Rigidly mounted with respect tothe traction 45 wheels, are the driving gears I 5, as usual. Meshing with the driving gears are the pinions I6, these being rigidly mounted on the shaft I1, which also carries, rigidly mounted thereon, the sprocket wheels i8, vand 4the conveyor Vwheels IES. 50

The conveyor system of 'the implement consists preferably oi a front conveyor web .20 and a rear conveyor web 2|, these webs being prefer- :ably made of transverse bars 24, spaced apart from one .another ,and; haying their 4ends ilexibly .5.5

interlocked with conveyor chains 25 and 26, respectively. The conveyor web 20 extends around and is driven by the conveyor wheels I9, while the other conveyor web 2| extends around conveyor drive wheels 21 rigidly mounted on shaft 28, the latter carrying rigidly mounted sprocket wheels 29 driven by sprocket chains 30, the latter in turn, extending around the drive sprockets I8.

VAt the other end of the conveyor web 20, are idler wheels 3| carried on the shaft 32, and at the other end of the conveyor web 2 are idler wheels 34 carried on a shaft 35, the slack or return strand of the respective webs being supported on idlers 36 and 31. The conveyor web 20 operates between two side walls 38, and the conveyor webY 2|, between two side walls 39, all of these side walls forming part of the framework of the digger.

The draft gear at the forward part of the implement, may consist of a yoke 4D having its lower end pivoted on the shaft 32, and its upper and front end fastened to a draft head 4 I. The latter hasrswiveled within it, a fork 42 extending down on either side of a grooved pilot wheel 43 to engage an axle 45. The present drawing shows a horse-drawn implement, and therefore, the draft bar `4I may be provided with a clevis 44 to which the usual doubletree (not shown) may be attached. Thertongue 46, which is indicated in the unhitched position, may be pivotally connected to the fork 42, by means of a pair of yoke members 41.

A digging blade 48 projects forward from the frame 38 and is preferably rigid therewith, being positioned so as to operate immediately in the rear of the pilot wheel 43. The draft yoke 40 may be adjustably held in certain rigid positions with respect to the frame, by means of a ratchet lever 50 which is rigidly mounted on a shaft 52. This lever may be Vengaged by a notched quadrant 5I and shaft 52 may carry short arms 53, which latter are pivoted to connecting straps 54 vwhose other ends may be adjustably pinned, for example at 56, to the draft yoke 40.

lAny desiredplurality of holes, such as those indicatedv at 51, may be provided to receive the pin 56 for various adjustments, in order to regulate the depth to which the digging blade may be set. By means kof the lever 50, the digging yoke 40Vrnay be swung backward or forward in relation to the frame 38, thereby varying the position of the digging blade from the maximum depth, through different degrees, to a point where it is lifted entirely out of the ground for the purpose of idling the implement when going to and from the eld. This operation of course, lifts the conveying web 20 simultaneously with the digging blade.

VThe conveyor web 2| may be lifted, when idling, by means of a ratchet lever 58 engaging a quadrant 59, and connected by rods or chains 60, to any suitable point of the frame 39.

In using this implement, the operator may occupy a seat 6I, supported on a spring blade 62 which isattached to the framework. By manipulating the lever 50, the digging blade 48 may be Yconveyor web 2U, and conveyed backwardly over 'the barsV 24, where the earth is shaken through `the' spaces between the bars, leaving the ro0t O11.

top of the conveyor strand, from where they are discharged onto the conveyor web 2|, and finally rolled oif over the shaft 21 at the rear of the machine.

In order to fully apprehend the advantages secured in my present invention, it is desirable to compare its operatively new performance with the performances of machines for a similar purpose, as heretofore constructed. I am fully aware that minor details of construction in my machine are not substantially different from those in machines which have long been sold in the open 'marken but I may particularly state that the novelty of my improved machine consists in locating the entire conveyor web system entirely below the horizontal plane which coincides with the rotative axis of the traction wheels, and that this system is driven from a point a considerable distance forward from the drive axle, so that the conveyor web 20 discharges its load entirely below, and in front of, the drive axle. Thus, the other conveyor web 2| may be brought down very low close to the ground, and its inclination be made very slight, thus causing the potatoes to be thoroughly cleaned in a comparatively short travel, and the final drop to the ground to be negligible.

The travel over the upper strands of the conveyor web system in my machine, is only about one-half of what it is in potato diggers as heretofore constructed, which aids in reducing the mechanical injury to potatoes, to almost nothing.

Added to these advantages is the fact that the strip of earth which passes over the digger blade, together with the roots contained in the strip; need be elevated only to a nominal height, that is to say, to points considerably below the level of the axle I4. This results in a great saving in horsepower, due to the reduced lift of the load and to the reduced friction of the shortened conveyor web.

In order to give a definite basis of comparison, I may state that in all diggers including my own, the traction wheels ordinarily are of approximately the same diameter, and the machines are of approximately the same capacity, but from tests actually made in the field, side by side with my machine, and therefore under the same general conditions, a standard machine of a type largely used, required six large horses to pull the machine, and at the end of the day, the horses were thoroughly tired out, Whereas my improved machine required only four horses, and at the end of the day, these were only normally fatigued.

Comparing the operative results of the two machines in a particular case when harvesting the same variety of potatoes, the mechanical injury in the case of the standard machines was almost thirty per cent, while in the case of my improved machine, mechanical injury was practically zero. The diagram in Fig. 3 indicates the conveyor web system of my improved potato digger, and by means of the full-line arrows 64, shows the path taken by the potatoes. At the same time, the dotted arrows 65 show the path taken by the potatoes in standard machines hereinbefore referred to.

It is to be understood that all machines, including my own, are provided with means for agitating the conveyor webs under the potatoes for the purpose of shaking off the adhering earthy material. Since such agitating means form no part of my invention, and are besides @t old and Well known, they need not be illustrated here.

Having fully described my invention, what I claim is:

1. A root digging machine, including in combination, a pair of traction wheels having an axle, a digger blade in advance of said traction wheels, and a conveyor web system extending from the rear of the digger blade toI a point immediately in the rear of said traction wheels, the said conveyor web system being located entirely below the rotative axis of the said traction Wheels and having its greatest elevation in advance of the said rotative axis.

2. A root digging machine, including in combination, a pair of rotatable traction wheels spaced laterally apart from each other, a digger blade in advance of the traction wheels, a conveyor web extending from the rear of the digger blade to a point below the level, and ahead of, the rotative axis of the traction wheels, and a second conveyor Web below the discharge of the iirst conveyor web, the second conveyor web having its discharge immediately to the rear of the traction Wheels and close tothe ground.

3. A root digging machine, including in combination, a pair of traction Wheels having an axle, a digging blade in advance of the axle, and a conveyor-Web system disposed entirely below the level of said axle, said conveyor-web system extending back from the said digger blade to a suitable point of discharge but having its greatest elevation in advance of the axle, and means for driving the conveyor-web system due to the rotation of the traction wheels.

JESSE C. LI'I'ILE. 

